This invention relates to a swash plate type compressor used with devices for cooling a cabin in a motor vehicle, and more particularly to the construction of a swash plate type compressor wherein the outer peripheral walls of cylinders serve as a shell of the compressor body. In recent years the use of a multitudinous control systems for motor vehicles has placed limitations on the space for mounting auxiliary equipment and on the weight thereof as well. The compressor of an air conditioning system for a motor vehicle is no exception.
Swash plate type compressors are superior in character to reciprocating type compressors because the former are higher in performance and produce less noise and vibration. However, the former have the inherent disadvantages of being relatively large in size and requiring a multiplicity of parts. These are the problems which should be solved in popularizing the use of swash plate type compressors.
Several proposals have been made to solve the aforesaid problems. One of such proposals known in the art consists in splitting the shell of a swash plate type compressor in two halves and bringing the two halves in abutting relationship at the center, with sealing means such as an O-ring being provided to the abutting end portions of the two halves which are clamped together from opposite sides.
Some disadvantages are associated with the swash plate type compressor constructed as aforementioned. For one thing, the abutting portions of the two halves of the shell are generally complex in shape and consequently the sealing means tends to be dislodged from its position or to go away when an external force is exerted thereon in a direction at a right angle to the axis of the compressor, with a result that gaps are formed in the sealed portion. This has made assembling of the parts a complicated process. Moreover, the aforementioned disadvantages increase the possibilities of leakage of the refrigerant from the compressor.
Moreover, the presence of the abutting sealed surface in the center makes it necessary to provide two refrigerant inlet ports, one in the left and the other in the right. Since it is difficult, due to the aforesaid limitations placed on the space, to provide a linear pipe portion of the supply piping system in the vicinity of the inlet ports, it is difficult to provide a uniform flow rate of refrigerant to the left and right chambers. This produces the following defects:
(1) The lubricant supplied with the streams of refrigerant by floating in mist form in the refrigerant is unevenly distributed to the bearings arranged symmetrically with respect to the abutting sealed surface, so that irregularities are caused to occur in the lubrication of the bearings; PA1 (2) A variation is produced during one cycle of operation in the compression efficiency of a plurality of pistons which are generally used with this type of compressor, with the result that strain due to heat is produced in the cylinder blocks; and
(3) The synergystic effect of the defects described in (1) and (2) increases vibration which is produced by the movements of the pistons.